Synthesis of multisubstituted cyclohexenes and cyclopentenes via cascade Michael/aldol/annulative SuFEx/β-sultone desulfonation of β-arylethenesulfonyl fluorides

Abstract

The first β-sultone desulfonation-facilitated diastereoselective synthesis of functional cyclohexenes and cyclopentenes is described. Under the mediation of Cs₂CO₃, γ-ketomalononitriles reacted with β-arylethenesulfonyl fluorides through a cascade Michael addition/aldol reaction/annulative SuFEx click reaction/β-sultone desulfonation process to afford functionalized cyclohexenes in 40–99% yields with excellent cis-selectivity. In addition, β-ketomalononitriles undergo a similar cascade reaction with β-arylethenesulfonyl fluorides to produce functional cyclopentenes in 57–99% yields with excellent trans-selectivity. A possible mechanism was proposed based on control experiments and DFT calculations.